Piranhas are known for their razor-sharp teeth and relentless bite. (The word piranha literally translates to “tooth fish” in the Brazilian language Tupí.) Adults have a single row of interlocking teeth lining the jaw. True piranhas have tricuspid teeth, with a more pronounced middle cuspid or crown, about 4 millimeters tall.
The shape of a piranha’s tooth is frequently compared to that of a blade and is clearly adapted to suit their meat-eating diet. The actual tooth enamel structure is similar to that of sharks.
It’s not uncommon for piranhas to lose teeth throughout their lifetime. But, while sharks replace their teeth individually, piranhas replace teeth in quarters multiple times throughout their lifespan, which reaches up to eight years in captivity. A piranha with half of its lower jaw chompers missing isn’t out of the ordinary.

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